Surgical HF apparatuses are commonly known. As part of high-frequency surgery, they are increasingly applied apart from standard applications such as cutting or coagulating in further fields such as for closing hollow organs, connecting biological tissue or in the context of an ablation. In doing so, an electrosurgical instrument directs a high-frequency current (HF current) through tissue to be treated, which is altered thereby. In the course of these special applications, the HF delivery is automatically controlled, metered and ended by an HF generator to which the instrument is electrically connected, and not by the surgeon.
If in the context of the above-mentioned applications of ever increasing variety the electrosurgical instrument is to be variably applicable for differing types of tissue (small intestine, large intestine, rectum, stomach, esophagus), for varying numbers of tissue layers or different application types (resection, anastomosis), it is a must that there is the possibility to be able to make pre-adjustments on the associated HF generator/electrical current source, so that it can make specific or special process settings for the respective application. A wrong setting of certain process parameters may lead in some circumstances to an unsatisfactory result or even to damages on the patient. This is why it has to be ensured at any time that all process parameters are correctly adjusted before an activation of the apparatus.
The concepts for HF activation, i.e. for supplying the HF current to the instrument, are a central topic with HF apparatuses and are known from prior art. An HF activation without a corresponding operation by the user is prevented by various safety functions on the electrosurgical instrument and/or on the HF generator of the apparatus.
From U.S. Pat. No. 5,035,695, there is known a method and an instrument for electro-cauterizing including locking functions which allow for a safe operation of the instrument in case of manual control. By means of a manually operable slide, an electrode of the instrument can be moved from a rest position where it is retracted into the instrument to a cauterizing position in which it projects from the instrument. Here, a lockout switch automatically disconnects the electrode from an HF current source/HF generator, if it is in the rest position. If the electrode is in the rest position, the slide additionally represents a mechanical locking means for activation switches for the manual activation of the electrode, whereas the activation switches are released by the slide in the cauterizing position and can be manually operated. It is a disadvantage that locking and releasing the instrument is carried out manually by the user without consideration of a generator setting.
From the European patent application EP 2 168 517 A1, there is known a system and a method for the manual locking of hand switches of a manually operated electrosurgical clamp for coagulating and severing tissue. The clamp comprises two mutually movable jaw parts which are to be supplied with electric current for the coagulation of tissue. A hand switch has to be selectively and manually operated by the user of the clamp for its activation. A lockout switch is also to be manually operated by the user of the clamp from a first position in which an operation of the hand switch is possible, to a second position in which an operation of the hand switch and an activation of the clamp are not possible. In an alternative embodiment, both the hand switch and the lockout switch have to be electrically closed in order to allow for an activation of the clamp. It is a disadvantage that the manual locking and releasing of the instrument by the user is likewise performed without any feedback to the generator.
From WO2009/149799 A1 there is known a surgical apparatus for coagulation and/or for cutting biological tissue. It comprises a bipolar clamp with two jaw parts for applying HF current, an activation circuitry and an HF generator. The supply of the HF current to the clamp can be controlled by means of the activation switch. In order to guard against operating errors, the apparatus comprises a safety means which cuts off the supply of electric current to the clamp if its jaw parts assume a position which is unsuitable for coagulation. This is merely to prevent an unintentional activation of the clamp.
Finally, U.S. Pat. No. 4,655,215 discloses a monopolar electrosurgical scalpel including a manual control for selective cutting or coagulating processes, with the option that specific operational modes can be deliberately suppressed. The scalpel comprises a slide switch which can be moved to three different positions by the user and via which an activation switch can be locked or released. In a first position, the activation switch is blocked. In a second position, it is to be operated such that the blade of the scalpel is either provided with a coagulation current or with zero current. In a third position, the activation switch is released, so that the blade of the scalpel is supplied either with a coagulation current or a cutting current or also with zero current. Thus, the manual control ensures that any coagulation or cutting currents can be delivered to the scalpel only after a corresponding release by the surgeon. It is a disadvantage here that the activation/setting is performed manually by the user of the scalpel, without said process being linked with a safety function against a false setting.
If an HF apparatus, as described at the outset, is supposed to be used in numerous different applications, a variable and wide range of selecting process parameters is required. It has to be guaranteed, however, that prior to an HF activation of the apparatus or of the process, namely before suppling the HF current to the instrument, an input or a monitoring of the corresponding process parameters by the user of the apparatus has been made in order to avoid a false generator setting, as the case may be.
In the known solutions, HF instruments or apparatuses are operated with fixed process parameters and/or flows. Depending on the respective application, however, single or several of these parameters (e.g. the level and progression of the HF energy) may vary and have to or would have to be correspondingly adapted in order to successfully carry out the desired operation, on the one hand, and to avoid further damages to the tissue, on the other hand.
Apparatuses are also known which allow for a setting of the intensity of the HF process on the HF generator. This gives the operator the possibility to correct the output of the HF energy (slightly) upwards or downwards. After an alteration of process parameters, all subsequent activations will then be carried out with these parameters until a new setting is made. There is the risk to forget to manually/visually check the process parameters or to adjust them correspondingly, although the conditions or requirements in the applications to be performed subsequently may differ from those of the previous application.